374 Sir george shuckburgh on the Variation 
alfo a fimilar error of fomething more than one quarter 
of a degree in laying down the freezing point fo that the 
fundamental interval between freezing and boiling, 
when the barometer hands at 29,8 inches (the mean 
height at London) was 1 8o°,7 1 inhead of 1 8o° ; by this 
means each divifion was in fa£t ^th part lefs than a de- 
gree : this frnall correction may therefore eafily be ap- 
plied, if thought neceffary, but 1 have taken no notice 
of it. 
I will now add a general table for the ufe of artihs in 
making this inftrument, both according to my own 
obfervations, and thofe of Mr. de luc, that the pre- 
ference may be given as it ihall be thought due; not 
that it is a matter of any great confequence which is 
made ufe of under fmall variations of the atmofphere; 
but even under thefe circumftances, I flatter myfelf, that 
the obje£t of this paper will be fufficiently obvious to 
all who wifh to verify a new theory, or aim at accuracy 
in thefe days of precifion. 
Height 
